Electric-railway system.



No. 650,952. Patented June 5, I900. W. ROBINSON.

ELECT BIC RAILWAY SYSTEM.

(Application filed Feb. 23, 189B.)

(NoModeL) *f HI WITNESSES INVENTU t ITED STATES PATENT Orrrcss \VILLIAM ROBINSON, OE BOSTON, MASSACHUSETTS.

ELECTRIC-RAILWAY SYSTEM.

SPECIFICATION forming part of Letters Patent N 0. 650,952, dated June 5, 1900.

Application filed February 23, 1898. Serial No 671,250. (No model.)

To all whom it may concern..-

Be it known that I, WILLIAM ROBINSON, a

citizen of the United States, residing in Boston,

in the county of Suffolk and State of Massachusetts, have in vented a new and Im proved Electric-Railway System, of which the following is a specification.

The nature of my invention will be under the usual form, and B a third rail or workingconductor made in sections a b a, separated or insulated from each other, as shown at d e. G is an electric generator, and O a feed-wire proceeding therefrom and extending along The magnets D E F, respectively, are electrically connected to the respective the line.

sections a b c of the working conductor B and also to the feed-wire C through the wires ff", g g, and h 7t, all as shown. The magnets are provided with and control the movement of the armature-levers t' 10 Z.

The railroad-trackA A is connected by the conductor H to the generator G, said track forming the return-conductor.

I is an electric motor-car or locomotive provided with the driving-motor M and the current-collecting brush or shoe m, which latter makes traveling contact with the sections of the working conductor B.

The armature-levers '6 is Z are arranged to make a short or direct circuit between the feed-wire O and the sections of the working conductor 13 when said magnets are magnetized 5' but the short circuit through these are mature-levers is normally open, as shown at the contact-points n and q q.

The collecting-shoe m is connected by the wire r to the drumor distributing-sections of the controller K, which is carried on the car in the usual manner, and the motor M is connected in like manner by the conductor 8 to the contact-sections s of said controller. The controller K in the drawing shows the circuit completed between the conductors r 3, thus completing the round circuit from the feedwire 0 through the controller and motor back to the generator.

The operation is as follows: As soon as the motor-car I enters upon the section b of the working conductor and the shoe m comes in contact with said section with the circuit closed through the controller K the circuit is instantly completed from the 'feedwire 0 through the magnet E, working section 1), controller K, motor M, wheels and axles of the car, and the track or return conductor A to the generator G. A very heavy current is thus passed through the magnet E, enabling it to attractits armature from a considerable distance, closing the circuit at the contactpoints 19,, and thus making a direct electrical connection of low resistance between the feedwire 0 and the working section b. When the contact-points p are brought together, most of the current is diverted from the magnet E and passes over the alternative route of lower resistance, including the contact-points 1). Nevertheless the magnet E is so balanced that it will retain sniiicient magnetism to retain its armature and keep the circuit closed at the points p after having closed the same. Thus it will be seen the magnet-circuitoffers practically no resistance to the passage of the current to the motor, since said current passes directly over the armature-lever k, as described, the resistance of which is merely nominal. If found of advantage or desirable, however, a slight resistanceo may. be placed in the armature-circuit, just enough to render it impossible to entirely short-circuit the current from the magnet'D, thus simplifying the proper balancing. of the switching-circuit. As soon as the carI passes I to the next section and the shoe m passes off the workingsection b the working circuit is opened between said working section b and the return conductor A, and consequently the current ceases simultaneously to flow through the magnet E and its armature-lever is. As a consequence the spring t instantly withdraws the armature-lever it, thus separating the points at p and leaving no electrical connection between the feed-wire C and said working sectionb, except through the magnet E. 4

By putting a sufficiently-heavy resistance in the magnet E or a sufficient supplemental resistance in the magnet-circuit, as shown at L in connection with the magnet D, all danger of shocks to pedestrians or animals is reduced to a minimum oraltogether eliminated, even when they step on the free sections of the working conductor and on the returnconduetor at the same time. It will be observed, furthermore, that when the train is coasting or is stopped at a station or elsewhere the circuit through the motor is necessarily opened by the controller Kthat is, the circuit is open between the working section I) and the return-comluctor A, and consequently through the magnet E and its armature-lever 7t, and the contact-points at p are therefore separated, owing to the demagnetization ofsaid magnet. Itise\ident,therefore, that there is no more danger in stepping on or touching any conductors within reach in the vicinity of a coasting or standing train than there is in stopping on the same conductors when the train is absent and the track clear.

Since the circuit is always first opened between the workingand the return conductors, it is evident that at the time the contactpoints at p are separated there is no current passing between them. Consequently there can be no burning or arcing between said points. Nevertheless in order to guard against the possibility of injuriousarcing or burning through accident or otherwise and also to insure better contact I prefer to make themagnet, with its connections, in the form of a quick-acting automatic switch, as shown in the drawing in connection with the magnet F. Here the armature-leverl is provided with the knifeblade section q, while thecontact portions q are made in the form of double spring blades or clips.

\Vhen the magnet F is magnetized and attracts its armature, therefore, the blade (1 is thrust between the spring-blades q, spreading them apart and making a good frictional and electrical spring connection between the parts.

\Vhen the magnet F is demagnetized, a powerful spring it withdraws the lever Z so quickly and separates the contact blades q q so far apart that the are cannot follow and bridge the gap, and consequently, if formed atall, it will be instantly snuffed out.

It has already been pointed out that the current which normally magnetizes the magnets is so strong and magnetizes them so powerfully as to enable them to attract their armatures a considerable distance. Consequently there is noditiiculty in constructing the switch with the contact-blades q q arranged to separate so far as to insure the instant breaking of any are that might by any means be formed between them.

In the description thus far the sectional working conductor B is assumed to be supported on the railroad-ties and the system to be operated under steam-railroad conditions.

Nevertheless it is evident that the conductors A B may be carried in a conduit orarranged in any suitable and advantageous manner or place without departing from the substance or spirit of my invention. Furthermore, in the description and drawing only one magnetic switch is shown in connection with each section of the working conductor; but in some cases several such switches may be advantageously used in connection with very long sections of the working conductor-for instance, in connection with the ordinary overheadtrolley systems. In this case a car would operate the nearest switch, thus obtaining a heavy working current through its shunt, whereas the potential of the working conductor would be so much lower near the more distant switches that they would remain in their normal condition until the mo tor-car came near, when they too would be operated in turn. By this arrangement the heavy working current on such systems would be concentrated near the car using it, instead of being dissipated, as at present, over long sections of wire, consuming current by their resistance. 'lhisarrangement would also practically eliminate danger to firemen from the trolley-wire, since in case of fire all cars of course in the vicinity would be stopped and the shunt circuits therefore open. Consequently there could be no dangerous current on the trolley-wire. Nevertheless in this case, as in others, it would be safer and preferable to have the trolley-wire or working conductor made in short sections and have one magnetic switch, as described, to each section.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent", is

1. In an electric-railway system, the combination, substantially as described, of an electrie generator, a feed-wire proceeding therefrom, the working conductor made in successive sections separated or insulated from each other, a return conductor, electromagnets having their opposite terminals connected to said feed-wire and to the respective sections of the working conductor, the circuit through said magnets being normally open, ar-matu res controlled by said respective magnets and arranged to open and close shunt-circuits around said magnets, means for proportionally balancing said respective magnetic and shunt circuits whereby the closing of circuit through said magnets will cause a predetermined or suit-able proportion of the current to flow through each of said respective magnetic and shunt circuits as long as said respective magnets remain magnetized.

2. In an electric-railway system, the combination, substantially as described, of a feedwire, the working conductor formed in successive sections, separated or insulated from each other, eleetromagnets having their opposite terminals connected respectively to said feed-wire and to the respective sections IIC of the working conductor, the circuits through said magnets being normally open, armatures controlled by said respective magnets and arranged to operate shunt-circuits between said feed-wire and said respective sections of the working conductor, means for proportionally balancing said magnets and shunt-circuits whereby the closing of circuit through said respective magnets will cause a predetermined or suitable proportion of the current to flow through each of said magnetic and shunt circuits as long as said respective magnets remain magnetized, and traveling contact devices making electrical connection between said working-conductor sections and the return-conductor, thus closing circuit through the respective magnets in succession.

3. In combination, substantially as described, a source of electric supply, an-electromagnet connected thereto, the circuit through said magnet being normally open, the armature arranged to form a shunt-circuit around said cluded in said shunt-circuit, the closing of the circuit through said magnet and the consequent attraction of its armature causing the greater part of the current to pass through said shunt-circuit andthe balance through the magnet, said shunt circuit remaining closed as long as said magnet remains magnetized. v

4. In an electric-railway system, the combination, substantially as described, of a feedwire connected to a stationary generator, a working conductor, an electromagnet directly connected to said conductor and to said feed- Wire and receiving initial current therefrom, an armature-lever controlled by said magnet and operating a shunt-circuit of low resistance between said feed-wire and working conductor, a motor-car receiving operative current from said feed-wire through said Working conductor, and a switch on said motorcar arranged to open and close circuit through the motor, the opening and closing of said motor-circuit operating to simultaneously open and close the magnetic and shunt circuits.

5. In an electric-railway system, the combi: nation, substantially as described, of the feed- Wire receiving current from a stationary generator, the working conductor made in sections, the return-conductor, an electromagnet having its opposite terminals directly connected to said feed-wire and to a section of said Working conductor, said magnet receiving initial current from the stationary generator, an armature-lever controlled by said magnet and operating a shunt-circuit of low resistance between said feed-wire and section of working conductor, said shunt-circuit and -mined or suitable magnet, and a resistance in:

the circuit of said magnet being normally open, a traveling motor arranged to establish electrical connection between said working section and the return-conductor, and a travelin g car-controller arranged to open and close circuit through the motor, the opening and the closing of the motor-circuit operating to simultaneously open and close the magnetic and shunt circuits.

6. The magnetic switch consisting, essentially, of the magnet, with its armature arranged in shun t-circuit relatively thereto, and means for proportionally balancing said magnetic and shunt circuits wherebya predeterproportion of the current is caused to How through each of said circuits, the terminals of said magnetic and shunt circuits being so connected and arranged that the whole of the current passing between said terminals will be divided proportionally between said magnetic and shunt circuits as long as the circuit of said magnet is'closed, substantially as described.

7. The magneticswitch consisting, essentially, of the electromagnet included in a circuit of high resistance, its armature, ar ranged in shunt-circuit relatively to said magnet, and a low resistance included in said shunt-circuit, the terminals of said magnetic and shunt circuits being so connected and arranged that the whole of the current passing between said terminals will be divided proportionally between said magnetic and shunt circuits as long as the circuit through said magnet remains closed and said magnet magnetized, the closing of the shunt-circuit causing the greater part of the current to pass over said shunt, leavinga smaller proportion of the current in the magnet, substantially as described.

8. The magnetic switch consisting, essentially of the magnet with its armature arranged in shun t-circuit relatively thereto, and means for proportionally balancing the resistance of said magnetic and shunt circuits, the terminals of said magnetic and shunt circuits being so connected and arranged that the whole of the current passing between said terminals will be divided proportionally between said magnetic and shunt circuits as long as the circuit of said magnet is closed, said switch having one element provided with spring-clip contact-pieces and the other with a knife-blade contact-piece arranged to press firmly between said spring-clips, substantially as described.

WILLIAM ROBINSON.

YVitnesses:

HAROLD W. SIMoNDs, ANGUS MCDONALD. 

